我在网上找到了这个文件选择器，开发人员说人们可以根据需要使用它。因为我认为代码很容易理解 - 我决定使用它并为我的应用程序稍微改变它。所有功劳归于原始开发人员（https://github.com/mburman/Android-File-Explore）
loadFileList();
showDialog(DIALOG_LOAD_FILE);
Log.d(TAG, path.getAbsolutePath());
}
private void loadFileList() {
try {
path.mkdirs();
} catch (SecurityException e) {
Log.e(TAG, "unable to write on the sd card ");
}
// Checks whether path exists
if (path.exists()) {
FilenameFilter filter = new FilenameFilter() {
public boolean accept(File dir, String filename) {
File sel = new File(dir, filename);
// Filters based on whether the file is hidden or not
return (sel.isFile() || sel.isDirectory())
&& !sel.isHidden();
}
};
String[] fList = path.list(filter);
fileList = new Item[fList.length];
for (int i = 0; i < fList.length; i++) {
fileList[i] = new Item(fList[i], R.drawable.file_icon);
// Convert into file path
File sel = new File(path, fList[i]);
// Set drawables
if (sel.isDirectory()) {
fileList[i].icon = R.drawable.directory_icon;
Log.d("DIRECTORY", fileList[i].file);
} else {
Log.d("FILE", fileList[i].file);
}
}
if (!firstLvl) {
Item temp[] = new Item[fileList.length + 1];
for (int i = 0; i < fileList.length; i++) {
temp[i + 1] = fileList[i];
}
temp[0] = new Item("Up", R.drawable.directory_up);
fileList = temp;
}
} else {
Log.e(TAG, "path does not exist");
}
adapter = new ArrayAdapter<Item>(this,
android.R.layout.select_dialog_item, android.R.id.text1,
fileList) {
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// creates view
View view = super.getView(position, convertView, parent);
TextView textView = (TextView) view
.findViewById(android.R.id.text1);
// put the image on the text view
textView.setCompoundDrawablesWithIntrinsicBounds(
fileList[position].icon, 0, 0, 0);
// add margin between image and text (support various screen
// densities)
int dp5 = (int) (5 * getResources().getDisplayMetrics().density + 0.5f);
textView.setCompoundDrawablePadding(dp5);
return view;
}
};
}
private class Item {
public String file;
public int icon;
public Item(String file, Integer icon) {
this.file = file;
this.icon = icon;
}
@Override
public String toString() {
return file;
}
}
@Override
protected Dialog onCreateDialog(int id) {
Dialog dialog = null;
AlertDialog.Builder builder = new Builder(this);
if (fileList == null) {
Log.e(TAG, "No files loaded");
dialog = builder.create();
return dialog;
}
switch (id) {
case DIALOG_LOAD_FILE:
builder.setTitle("Choose your file");
builder.setAdapter(adapter, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
chosenFile = fileList[which].file;
File sel = new File(path + "/" + chosenFile);
if (sel.isDirectory()) {
firstLvl = false;
// Adds chosen directory to list
str.add(chosenFile);
fileList = null;
path = new File(sel + "");
loadFileList();
removeDialog(DIALOG_LOAD_FILE);
showDialog(DIALOG_LOAD_FILE);
Log.d(TAG, path.getAbsolutePath());
}
// Checks if 'up' was clicked
else if (chosenFile.equalsIgnoreCase("up") && !sel.exists()) {
// present directory removed from list
String s = str.remove(str.size() - 1);
// path modified to exclude present directory
path = new File(path.toString().substring(0,
path.toString().lastIndexOf(s)));
fileList = null;
// if there are no more directories in the list, then
// its the first level
if (str.isEmpty()) {
firstLvl = true;
}
loadFileList();
removeDialog(DIALOG_LOAD_FILE);
showDialog(DIALOG_LOAD_FILE);
Log.d(TAG, path.getAbsolutePath());
}
// File picked
else {
chosenFile = fileList[which].file;
File test = new File(path + "/" + chosenFile);
sendback(test);
}
}
});
break;
}
dialog = builder.show();
return dialog;
}
对不起，如果它有点太长了。但这就是 onCreate() 中的整个文件选择器。我使用以下代码打开它：
Bundle b = new Bundle();
b.putInt("tallet", 1);
Intent i = new Intent(getApplicationContext(), FileExplore.class);
i.putExtras(b);
startActivityForResult(i, 0);
该代码完美运行。但是当我按“返回”（onBackPressed）时，如果我说完成（），它会给我空白（黑色）屏幕；. 现在我正在使用这段代码：
@Override
public void onBackPressed() {
// TODO Auto-generated method stub
super.onBackPressed();
Intent backIntent = new Intent(FileExplore.this, AndroidTabLayoutActivity.class);
startActivity(backIntent);
}
这实际上有效，但是如果我按一次后退，然后再按一次菜单，当我再次按后退按钮时，它会给我黑屏。编辑：它在第二次后按时进入 onBackPressed 代码，而不是第一次。
这是我在 PhotosActivity 中的 onActivityResult 代码（它是一个选项卡布局 - photosactivity 只是其中一个屏幕）：
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
// Bundle b = getIntent().getExtras();
if (resultCode == -1)
{
Bundle b = data.getBundleExtra("FiletoPhoto");
int knappen = b.getInt("number");
String titlen = b.getString("title");
{
Listofsounds los = new Listofsounds();
String shortname = los.puttextonit(titlen, knappen);
putnameinit(shortname,knappen);
}
}
else if (resultCode == 0)
{
//If I press "back" i've made the resultCode to be 0 in the onBackPressed. What should I do here then?
}
}
我应该怎么做才能按一次它并返回菜单？